High density thermal ink jet printhead

An ink jet printhead (11) composed of two substantially two identical parts (28) and method of batch fabricating the parts. Each part (28) has V-grooves (29) anisotropically etched between a linear array of heating elements (30) having selectively addressable electrodes (33) which are parallel to each other. The grooved structures of the parts (28) permit them to be mated face-to-face, so that they are automatically self-aligned by the inter-meshing of the lands (31) containing the heating elements (30) on one part (28) with the grooves (29) of the other part (28). A pair of parts (28) may be used as a printhead for a carriage type ink jet printer or a plurality of parts (28) may be assembled for a pagewidth printer. The pagewidth printhead is assembled by offseting the first two parts (28) a selected number of grooves (29) when they are mated so that the subsequently added adjacent parts (28) abut each other and yet are self-aligned with the confronting parts (28).